Up to now, there is a possibility that an error occurs due to external noise or the like in media for storing and transmitting digital data, for example. For this reason, quality inspections are conducted on the media before being shipped as products.
In HDD recording media, for example, a predetermined pattern for defect scanning is conventionally written into the entire surface to thereby conduct various inspections.
Incidentally, in the case of reading digital data from recording media, an error correction code is used to detect and correct an error occurring in the digital data. In the error correction code, redundant data is added to the data during encoding, and the error of the data is corrected based on the redundant data during decoding.
In the case of detecting and correcting the error using the error correction code, however, a decoding target sequence needs to be code words. When error detection and correction is to be performed on digital data read from recording media, for example, it is necessary to preliminarily write code words in the recording media. If the pattern for defect scanning, which is written for inspection, is not represented by code words, it is necessary to rewrite the entire surface of the recording media. This cases a problem in that the inspection time during shipment of products is increased and the load on the inspection is heavy.